X-ray tube operating state acquiring device, x-ray tube operating state acquiring system, and x-ray tube operating state acquiring method

ABSTRACT

An X-ray tube controller measures operation information (filament power supply time in an X-ray tube and a grid voltage value applied to grid electrodes to maintain the tube current value under a predetermined tube voltage). The information is transmitted to an X-ray tube operation information acquiring unit via a communication line. In a storage section of the information acquiring unit, a database written with degree of attrition corresponding to the integrated power supply time of a filament (reduction ratio of thermalelectron emission amount (tube current value at a predetermined G1 voltage) to the initial value (thermalelectron emission amount when the filament is first used) is stored. An attrition degree determination section determines the degree of attrition of the filament from the count of filament power supply time with reference to the database. Also, the attrition degree determination section determines the end of life from the G1 voltage value.

TECHNICAL FIELD

The present invention relates to an X-ray tube operation statusacquiring unit, an X-ray tube operation status acquiring system and anX-ray tube operation status acquiring method.

BACKGROUND ART

Manufacturers or maintenance services providers of X-ray tube arerequired to detect the cause of failure on X-ray tube. That is, it isrequired to detect attrition of parts or occurrence of abnormaloperation on X-ray tube and to replace or repair the parts of the X-raytube. Conventionally, the determination of degree of attrition of partsand detection of occurrence of abnormal operation are carried out in amanual manner.

To determine the degree of attrition of parts or to detect occurrence ofabnormal operation, it is useful to collect operation information aboutthe operation status of the X-ray tube, which is used for determining ofthe degree of attrition of parts or detecting occurrence of abnormaloperation. Conventionally, service person goes regularly to theinstallation site of the X-ray tube, and collects the operationinformation.

DISCLOSURE OF THE INVENTION

However, there resides such problem in the conventional method thatconsiderable work and time are required for detecting the cause offailure of the X-ray tube.

The present invention has been proposed to solve the above problems. Anobject of the present invention is to provide an X-ray tube operationstatus acquiring unit, an X-ray tube operation status acquiring systemand an X-ray tube operation status acquiring method, which enables todetect the cause of failure of X-ray tube with a small work and time.

To achieve the above object, an X-ray tube operation status acquiringunit according to the present invention comprises receiving means forreceiving operation information about operation status of an X-ray tubetransmitted from an X-ray tube measuring apparatus for measuring theoperation status of the X-ray tube via a communication line, and storingmeans for storing the operation information received by the receivingmeans.

Also, to achieve the above object, an X-ray tube operation statusacquiring method according to the present invention comprises areceiving step in which receiving means receives operation informationabout operation status of the X-ray tube transmitted from an X-ray tubemeasuring apparatus for measuring the operation status of the X-ray tubevia a communication line, and a storing step in which storing meansstores the operation information received by the receiving means.

After the receiving means obtains the operation information about theoperation status of the X-ray tube measured by X-ray tube measuringapparatus via the communication line, the storing means stores theoperation information. Accordingly, it is possible for service person todetect the cause of failure on the X-ray tube without necessity of goingto the installation site to inspect the X-ray tube. As a result, thecause of failure of the X-ray tube can be detected with small work andtime.

In the X-ray tube operation status acquiring unit and the X-ray tubeoperation status acquiring method according to the present invention,the operation information preferably includes filament power supplytime.

The filament deteriorates in proportion to the power supply time. Sincethe operation information includes the filament power supply time, thedeterioration of the filament can be detected from the count of thefilament power supply time.

In the X-ray tube operation status acquiring unit and the X-ray tubeoperation status acquiring method according to the present invention,the operation information preferably includes a level of a grid voltageapplied to grid electrodes so as to maintain the value of the tubecurrent flowing to a target to a certain level in a state where apredetermined tube voltage is applied to the target of the X-ray tube.

When the filament deteriorates, to maintain the specific tube currentvalue in a state where a predetermined tube voltage is applied thereto,the grid voltage has to be increased. The deterioration of the filamentcan be detected from the level of the grid voltage included in theoperation information.

In the X-ray tube operation status acquiring unit and the X-ray tubeoperation status acquiring method according to the present invention,the operation information preferably includes X-ray irradiation time.

The target deteriorates in proportion to the X-ray irradiation time.Since the operation information includes the X-ray irradiation time, thedeterioration of the target can be detected from the count of the X-rayirradiation time.

In the X-ray tube operation status acquiring unit and the X-ray tubeoperation status acquiring method according to the present invention,the operation information preferably includes a strength of the X-raygenerated by thermoelectron collided with the target in a state where apredetermined tube voltage is applied to the target of the X-ray tubeand a predetermined tube current flows to the target.

When the target deteriorates, the strength of the X-ray generated undera specific tube voltage value and tube current value decreases. Thedeterioration of the target can be detected from the strength of theX-ray included in the operation information.

The X-ray tube operation status acquiring unit according to the presentinvention preferably comprises attrition degree determination means fordetermining the degree of attrition of component constituting the X-raytube based on the operation information. Also, the X-ray tube operationstatus acquiring method according to the present invention preferablycomprises an attrition degree determination step in which attritiondegree determination means determines the degree of attrition ofcomponent constituting the X-ray tube based on the operationinformation.

Since the attrition degree determination means determines the degree ofattrition of the component constituting the X-ray tube based on theoperation information, work and time for analyzing the operationinformation can be eliminated.

The X-ray tube operation status acquiring unit according to the presentinvention preferably comprises determination result notifying means fornotifying determination result by the attrition degree determinationmeans to an information communication terminal via a communication line.

Also, the X-ray tube operation status acquiring method according to thepresent invention preferably comprises a determination result notifyingstep, in which determination result notifying means notifiesdetermination result by the attrition degree determination means to aninformation communication terminal via a communication line.

Since the determination result notifying means notifies thedetermination result by the attrition degree determination means to theinformation communication terminal via the communication line, it ispossible to notify the necessity of preparation for componentreplacement to the user without requiring work or time.

The X-ray tube operation status acquiring unit according to the presentinvention preferably comprises abnormal operation detecting means fordetecting abnormal operation of the X-ray tube based on the operationinformation.

Further, the X-ray tube operation status acquiring method according tothe present invention preferably comprises an abnormal operationdetecting step, in which abnormal operation detecting means detectsabnormal operation of the X-ray tube based on the operation information.

Since the abnormal operation detecting means determines abnormaloperation of the X-ray tube based on the operation information, work andtime for analyzing the operation information can be eliminated.

In the X-ray tube operation status acquiring unit according to thepresent invention, the operation information preferably includes astrength of the X-ray generated by thermoelectron collided with thetarget of the X-ray tube in a state where a predetermined tube voltageis applied to the target of the X-ray tube and a predetermined tubecurrent flows to the target; the abnormal operation detecting meanspreferably detects occurrence of electric discharge phenomenon in theX-ray tube based on the strength of the X-ray.

Further, in the X-ray tube operation status acquiring method accordingto the present invention, the operation information preferably includesa strength of the X-ray generated by thermoelectron collided with thetarget of the X-ray tube in a state where a predetermined tube voltageis applied to the target of the X-ray tube and a predetermined tubecurrent flows to the target; the abnormal operation detecting meanspreferably detects occurrence of electric discharge phenomenon in theX-ray tube based on the strength of the X-ray.

When electric discharge phenomenon occurs in the X-ray tube, since thetarget deteriorates, the strength of the X-ray generated under aspecific tube voltage value and the tube current value decreases. Sincethe strength of the X-ray included in the operation informationdecreases sharply, the occurrence of electric discharge phenomenon inthe X-ray tube can be detected.

The X-ray tube operation status acquiring unit according to the presentinvention preferably comprises detection result notifying means fornotifying detection result by the abnormal operation detecting means toan information communication terminal via a communication line.

Further, the X-ray tube operation status acquiring method according tothe present invention preferably comprises a detection result notifyingstep, in which detection result notifying means notifies detectionresult by the abnormal operation detecting means to an informationcommunication terminal via a communication line.

Since the detection result notifying means notifies the detection resultby the abnormal operation detecting means to the informationcommunication terminal via the communication line, the occurrence ofabnormal operation can be notified to the user without any work or time.

The X-ray tube operation status acquiring unit according to the presentinvention preferably comprises presentation means for presenting theoperation information stored in the storing means on a display.

Also, the X-ray tube operation status acquiring method according to thepresent invention preferably comprises a presentation step, in whichpresentation means presents the operation information stored in thestoring means on a display.

Since the presentation means presents the operation information storedin the storing means on the display, service person can readily collectthe information about the operation status of the X-ray tube.

To achieve the above object, X-ray tube operation status acquiringsystem according to the present invention is an X-ray tube operationstatus acquiring system for controlling operation of X-ray tube,comprising: an X-ray tube measuring apparatus including measuring meansfor measuring operation status of the X-ray tube and transmission meansfor transmitting operation information of the X-ray tube obtained by themeasuring means by measuring the operation status of the X-ray tube toan information communication terminal via a communication line, andX-ray tube operation status acquiring unit as in any of claims 1-17,wherein receiving means of the X-ray tube operation status acquiringunit receives the operation information transmitted by transmissionmeans of the X-ray tube measuring apparatus; storing means of the X-raytube operation status acquiring unit stores the operation informationreceived by the receiving means of the X-ray tube operation statusacquiring unit.

To achieve the above object, another aspect of the X-ray tube operationstatus acquiring unit according to the present invention is an X-raytube operation status acquiring unit for obtaining operation informationabout operation status of an X-ray tube equipped with a filament foremitting thermoelectron by being supplied with power, comprising:inputting means for inputting operation information of the X-ray tubeoutputted from an X-ray tube measuring apparatus for measuring operationstatus of the X-ray tube and including at least filament power supplytime and value of grid voltage applied to grid electrodes so as tomaintain the value of tube current flowing to a target in a state wherea predetermined tube voltage is applied to the target of the X-ray tube,and an attrition degree determination means for determining degree ofattrition of the filament based on the filament power supply time andthe grid voltage value.

Also, another aspect of the X-ray tube operation status acquiring unitaccording to the present invention is an X-ray tube operationinformation acquiring method for obtaining operation information aboutoperation status of an X-ray tube equipped with a filament for emittingthermoelectron by being supplied with power, comprising: a first stepfor obtaining operation information of the X-ray tube outputted from anX-ray tube measuring apparatus for measuring operation status of theX-ray tube and including at least filament power supply time and valueof grid voltage applied to grid electrodes so as to maintain the valueof tube current flowing to a target in a state where a predeterminedtube voltage is applied to the target of the X-ray tube, and a secondstep for determining degree of attrition of the filament based on thefilament power supply time and the grid voltage value.

The degree of attrition of the filament can be determined from thefilament power supply time included in the operation information.Further, the attrition of the filament can be determined more preciselyfrom the grid voltage value included in the operation information.Accordingly, the attrition of the filament can be detected with a smallwork and time.

To achieve the above object, further another aspect of the X-ray tubeoperation status acquiring unit of the present invention is an X-raytube operation status acquiring unit for obtaining operation informationabout operation status of an X-ray tube, comprising: inputting means forinputting operation information of the X-ray tube outputted from anX-ray tube measuring apparatus for measuring operation status of theX-ray tube and including at lest X-ray irradiation time and strength ofX-ray generated by thermoelectron collided with a target in a statewhere a predetermined tube voltage is applied to the target of the X-raytube and a predetermined tube current flows to the target, and attritiondegree determination means for determining degree of attrition of thetarget based on the X-ray irradiation time and the strength of theX-ray.

Also, further another aspect of the X-ray tube operation statusacquiring method according to the present invention is an X-ray tubeoperation information acquiring method for obtaining operationinformation about operation status of an X-ray tube, comprising: a firststep for obtaining operation information of the X-ray tube outputtedfrom an X-ray tube measuring apparatus for measuring operation status ofthe X-ray tube and including at lest X-ray irradiation time and strengthof X-ray generated by thermoelectron collided with a target in a statewhere a predetermined tube voltage is applied to the target of the X-raytube and a predetermined tube current flows to the target, and a secondstep for determining degree of attrition of the target based on theX-ray irradiation time and the strength of the X-ray.

The degree of the attrition of the target can be determined from theX-ray irradiation time included in the operation information. Further,the attrition of the target can be determined more precisely from thestrength of the X-ray included in the operation information.Accordingly, the attrition of the target can be detected with a smallwork and time.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view schematically showing the structure of an X-ray tube 1(sectional view);

FIG. 2 is a diagram showing the functional configuration of an X-raytube operation status acquiring system according to a first embodiment;

FIG. 3 is a diagram showing the content of a file 321 about theattrition degree determination of a filament of the X-ray tube 1included in operation information;

FIG. 4 is a diagram showing the content of a file 322 about therelationship between G1 voltage value (initial value) and tube currentvalue of the X-ray tube 1, which is stored in a storage section 320beforehand;

FIG. 5 is a diagram showing the content of a file 323 about the X-rayirradiation time of the X-ray tube 1 included in the operationinformation;

FIG. 6 is a diagram showing the content of a file 324 about theover-time changes of the tube voltage value and tube current valueincluded in the operation information;

FIG. 7 is a diagram showing the content of a file 325 about therelationship among the tube voltage value, the tube current value andthe X-ray dosage (initial value) of the X-ray tube 1, which is stored inthe storage section 320 beforehand;

FIG. 8 is a diagram showing the content of a file 326 about the tubevoltage value, the tube current value and the X-ray dosage included inthe operation information;

FIG. 9 is a diagram showing the functional configuration of an X-raytube operation status acquiring system according to a second embodiment;and

FIG. 10A is a graph showing the filament power supply time; FIG. 10B isa graph showing the X-ray irradiation time; FIG. 10C is a graph showingthe changes of the G1 voltage value; and FIG. 10D is a graph showing thechanges of X-ray dosage (strength of the X-ray).

BEST MODES FOR CARRYING OUT THE INVENTION

Hereinafter, referring to the attached drawings, preferred embodimentsof an X-ray tube operation status acquiring unit, an X-ray tubeoperation status acquiring system and an X-ray tube operation statusacquiring method of the present invention will be described in detail.

First Embodiment

First of all, the structure and the operation of an X-ray tube 1, whichis controlled by the X-ray tube operation status acquiring system of afirst embodiment will be described.

FIG. 1 is a view schematically showing the structure of the X-ray tube 1(sectional view). As shown in FIG. 1, the X-ray tube 1 is sealed by anouter shell, which comprises a metal housing 11, a stem 12 and aberyllium window 13. The X-ray tube 1 is provided with a vacuum pump 14.Before activating the X-ray tube 1, gases within the outer shell aredischarged by the vacuum pump 14. When the X-ray tube 1 is a sealedtype, the inside of the outer shell is sealed in vacuum beforehand.

The X-ray tube 1 comprises, inside the outer shell, a filament 110 foremitting thermoelectron by being supplied with power, a first gridelectrode 120 for thrusting back the thermoelectron toward the filament,a second grid electrode 130 for pulling the thermoelectron toward thetarget, electromagnetic lenses 140 for focusing the beam ofthermoelectron and a target 150 made of tungsten for generating X-ray bythe thermoelectron collided therewith. The first grid electrode 120, thesecond grid electrode 130 and the electromagnetic lens 140 are disposedin this order from the filament 110 toward the target 150. The firstgrid electrode 120 and the second grid electrode 130 are provided withan opening 120 a and an opening 130 a respectively for allowing thethermoelectron to pass through in the center thereof.

The X-ray tube 1 is provided with a power supply 15, which includes ahigh voltage generating circuit for applying a positive high voltage tothe target 150.

The X-ray tube 1 is connected to an X-ray tube controller 2, which willbe described later, via a control cable 16, and is controlled by theX-ray tube controller 2.

When the power switch 21 of the X-ray tube controller 2 turns ON (X-rayirradiation switch 22 is OFF), each part of the X-ray tube 1 is suppliedwith power and the X-ray tube 1 begins to operate. When the filament 110is applied with a predetermined voltage and supplied with power, thethermoelectron is emitted. Also, the X-ray tube 1 begins warming up, andthe level of the voltage (tube voltage) applied to the target 150gradually increases up to a preset tube voltage value. Further thevoltage, which is applied to the first grid electrode 120, is controlledso that the current (tube current), which flows to the target 150,reaches a preset tube current value.

When the warming up is terminated, a negative voltage (cut-off voltage)is applied to the first grid voltage 110, and the X-ray tube 1 getsready to irradiate the X-ray. At this time, the thermoelectron emittedfrom the filament 110 is pulled by the second grid electrode 130, whichhas a potential higher than that of the filament 110. At the same time,since a cut-off voltage is applied to the first grid electrode 120, thethermoelectron is held so as not to pass through the opening 120 a ofthe first grid electrode 120.

When the X-ray irradiation switch 22 of the X-ray tube controller 2turns ON, the voltage value of the first grid electrode 120 rises, thethermoelectron is pulled by the second grid electrode 130; and thus, thethermoelectron passes through the opening 120 a of the first gridelectrode 120. Further, being accelerated by the tube voltage applied tothe target 150, the thermoelectron passes through the opening 130 a ofthe second grid electrode 130. And when the X-ray irradiation switch 22turns ON, by controlling the level of the voltage (G1 voltage) appliedto the first grid electrode, the amount of the thermoelectron passingthrough the openings 120 a and 130 a can be increased or reduced. Thatis, by controlling the level of the G1 voltage, the strength of the tubecurrent can be increased or reduced.

When the thermoelectron beam focused by the electromagnetic lens 140collides with the target 150, the target 150 generates X-ray. The X-raypasses through the beryllium window 130 and goes out to the outside ofthe X-ray tube 1. The strength of the X-ray generated by the target 150depends on the level of the tube voltage and the strength of the tubecurrent.

The X-ray tube, which is controlled by the X-ray tube operation statusacquiring system of the first embodiment, may be a sealed type or anopen type. In the X-ray tube 1, by supplying power to the filament, thethermoelectron is emitted. An X-ray tube provided with an indirectlyheated thermoelectron generator, which emits thermoelectron by heatingthe cathode by a heater, may be employed.

Next, the functional configuration of the X-ray tube operation statusacquiring system in the first embodiment will be described. FIG. 2 is adiagram showing the functional configuration of the system in the firstembodiment. As shown in FIG. 2, the X-ray tube operation statusacquiring system in the first embodiment comprises an X-ray tubecontroller 2 (X-ray tube measuring apparatus) and an X-ray tubeoperation status acquiring unit 3. The X-ray tube controller 2 islocated at the user site of the X-ray tube 1. The X-ray tube controller2 controls the X-ray tube 1 and measures the operation status of theX-ray tube 1. Also, the X-ray tube controller 2 has a function totransmit the operation information about the operation status of theX-ray tube 1 to the X-ray tube operation status acquiring unit 3 via acommunication line. Further, at the user site of the X-ray tube 1, aninformation communication terminal 4 is installed. The informationcommunication terminal 4 has a function to obtain notificationinformation, which is transmitted from the unit 3 via a communicationline to present the information to the user. The X-ray tube operationstatus acquiring unit 3 is located at the site of the management andmaintenance provider of the X-ray tube 1, and has a function to controlthe X-ray tube 1 via a communication line.

The X-ray tube controller 2 is connected to the X-ray tube 1 via thecontrol cable 16. The X-ray tube controller 2 comprises a power switch21, which changes over between activation and shutoff of the X-ray tube1, the X-ray irradiation switch 22, which changes over betweenirradiation and standby of the X-ray during activation of the X-ray tube1, a tube voltage adjusting section 23, which adjusts the level of thetube voltage, a tube current adjusting section 24, which adjusts thestrength of the tube current, a communication section 210 (transmissionmeans, receiving means), which has a function to communicate with theX-ray tube operation status acquiring unit 3 via the communication line,a measuring section 220 (measuring means), which measures the operationstatus of the X-ray tube 1 and a memory 230, which stores the operationinformation.

As described above, when the power switch 21 turns ON, the power issupplied to each part of the X-ray tube 1, and the X-ray tube 1 beginswarming up. During the standby of irradiation of the X-ray, when theX-ray irradiation switch 22 turns ON, the voltage value of the firstgrid electrode switches from the cut-OFF voltage value to the G1 voltagevalue. Thereby, the tube current flows and the target 150 generates theX-ray. By using the up-button and the down-button in the tube voltageadjusting section 23, the preset tube voltage of the X-ray tube 1 can beadjusted. Likewise, by using the up-button and the down-button in thetube current adjusting section 24, the preset tube current of the X-raytube 1 can be adjusted. The measuring section 220 measures the operationstatus of the X-ray tube 1 and obtains the operation information aboutthe operation status of the X-ray tube 1. As for the content of theoperation information, a description will be given in the description ofthe operation status of the X-ray tube operation status acquiring systemof the first embodiment, which will be described later. The measuringsection 220 is provided with an X-ray monitor 221, which has a functionto measure the strength of the irradiated X-ray of the X-ray tube 1 inthe operation status. The X-ray monitor 221 is connected to the X-raytube controller main body via a cable, and is located in an irradiationarea of the X-ray of the X-ray tube 1. The operation informationobtained by the measuring section 220 is stored in the memory 230. Thecommunication section 210 transmits the operation information stored inthe memory 230 to the X-ray tube operation status acquiring unit 3 via acommunication line when the activation of the X-ray tube is terminatedor at specific intervals.

The X-ray tube operation status acquiring unit 3 comprises acommunication section 310 (transmission means, receiving means,inputting means), a storage section 320 (storing means), an attritiondegree determination section 330 (attrition degree determination means),an abnormal operation detecting section 340 (abnormal operationdetecting means), a notification section 350 (determination resultnotifying means, detection result notifying means) and a presentationsection 360 (presentation means).

The communication section 310 receives operation information, which istransmitted from the X-ray tube controller 2 via the communication line.The storage section 320 stores the operation information received by thecommunication section 310. The attrition degree determination section330 determines the degree of attrition of the filament 110 and thetarget 150 of the X-ray tube 1 based on the operation information storedin the storage section 320. The abnormal operation detecting section 340detects electric discharge phenomenon in the X-ray tube 1 based on theoperation information stored in the storage section 320. Thenotification section 350 notifies the determination result by theattrition degree determination section 330 and the detection result bythe abnormal operation detecting section 340 to the informationcommunication terminal 4 via the communication line. The presentationsection 360 presents the operation information stored in the storagesection 320 on a display.

Next, a first operation (an operation in which the attrition degreedetermination section 330 determines the degree of attrition of thefilament 110 based on the filament power supply time) of the X-ray tubeoperation status acquiring system according to the first embodiment andthe effect thereof will be described.

FIG. 3 is a diagram showing the content of a file 321 about theattrition degree determination of the filament 110 included in theoperation information. As shown in FIG. 3, the file 321 comprises anactivation start date and time field, an activation terminate date andtime field, a filament power supply time field, an X-ray irradiationtime field and a G1 voltage value field.

When the power switch 21 of the X-ray tube controller 2 turns ON, apredetermined voltage is applied to the filament 110. The measuringsection 220 counts the time (filament power supply time) from the pointwhen the power switch 21 turns ON.

The activation start date and time (the time when the power switch 21turns ON), the activation terminate date and time (the time when thepower switch 21 turns OFF), the filament power supply time, the X-rayirradiation time and the G1 voltage value when the irradiation of theX-ray is terminated last are recorded in the file 321 stored in thememory 230 respectively.

The file 321 is transmitted to the X-ray tube operation status acquiringunit 3 when the activation of the X-ray tube 1 is terminated. When thecommunication section 310 in the X-ray tube operation status acquiringunit 3 receives the file 321, the file 321 stored in the storage section320 is updated.

The attrition degree determination section 330 counts the filament powersupply time with reference to the file 321. In the storage section 320,a database, written with the degree of attrition corresponding to theintegrated power supply time of the filament 110 (the reduction ratio ofthermalelectron emission amount (tube current value at a predeterminedG1 voltage) relative to the initial value (thermalelectron emissionamount when the filament 110 is first put to use)) is stored. Theattrition degree determination section 330 determines the degree ofattrition of the filament 110 from the integrated power supply time withreference to the database. Here, the attrition degree determinationsection 330 may determine the degree of attrition of the filament 110while taking the count of the X-ray irradiation time recorded in thefile 321 into consideration.

When the degree of attrition of the filament 110 to be determined by theattrition degree determination section 330 has reached a predeterminedvalue (for example, the count of the filament power supply time: 10,000hours, the degree of attrition of the filament 110: 80%), thenotification section 350 notifies the degree of attrition of thefilament 110 to the information communication terminal 4, and transmitsa notification to prompt the preparation for replacement of the filament(in the case of the sealed type, X-ray tube head).

The presentation section 360 is provided with the display, and presentsthe file 321 on the display.

Since a predetermined voltage is applied to the filament 110, thefilament 110 deteriorates in proportion to the count of the filamentpower supply time. Therefore, the X-ray tube operation status acquiringunit 3 can detect the deterioration of the filament 110 from the countof the filament power supply time. As a result, the cause of failure ofthe X-ray tube 1 can be detected (deterioration of the filament 110)without work or time of a service person. When the informationcommunication terminal 4 receives the notification transmitted from thenotification section 350, service person can notify the deterioration ofthe filament 110 to the user before the filament 110 reaches the end oflife without work or time to prompt the preparation for replacement ofthe filament (in the case of sealed type, X-ray tube head). Since theoperation information is presented on the display, service person canobtain the information about the operation status of the X-ray tube 1.

When the X-ray is irradiated and when the X-ray is not irradiated, theattrition ratio of the filament per filament power supply time differs.However, the attrition degree determination section 330 can determinethe degree of attrition of the filament taking the count of the X-rayirradiation time recorded in the X-ray irradiation time field of thefile 321 into consideration.

Next, a second operation (an operation in which the attrition degreedetermination section 330 determines the degree of attrition of thefilament 110 based on the level of the grid voltage) of the X-ray tubeoperation status acquiring system according to the first embodiment andthe effect thereof will be described.

FIG. 4 is a diagram showing the content of a file 322 about therelationship between the G1 voltage value (initial value) and the tubecurrent value of the X-ray tube 1, which is stored beforehand in thestorage section 320. As shown in FIG. 4, the file 322 comprises a G1voltage value field and a tube current value field. In the G1 voltagevalue field, G1 voltage values (initial value) for achieving the tubecurrent values written in the tube current value field are written. Thewording “initial value” means the G1 voltage value when the filament 110is first put to use.

The attrition degree determination section 330 compares the latest G1voltage value recorded in the file 321 and the file 322, and computesthe reduction ratio of the absolute value of the latest G1 voltage valuerelative to the absolute value of the G1 voltage value (initial value)in the preset tube current value. In the storage section 320, a databasewritten with the degree of attrition (the reduction ratio ofthermalelectron emission amount (tube current value at a predeterminedG1 voltage) relative to the initial value (thermalelectron emissionamount when the filament 110 is first put to use)) corresponding to thereduction ratio of the absolute value of the G1 voltage relative to theabsolute value of the G1 voltage (initial value), is stored. Theattrition degree determination section 330 determines the degree ofattrition of the filament 110 from the reduction ratio of the absolutevalue of the latest G1 voltage relative to the absolute value of the G1voltage (initial value) with reference to the database.

When the degree of attrition of the filament 110 to be determined by theattrition degree determination section 330 has reached a predeterminedvalue (for example, the reduction ratio of the absolute value of the G1voltage relative to the absolute value of the G1 voltage (initialvalue): 80%, degree of attrition of the filament 110: 80%), thenotification section 350 notifies the degree of attrition of thefilament 110 to the information communication terminal 4, and transmitsa notification to prompt the preparation for replacement of the filament(in the case of the sealed type, X-ray tube head).

The presentation section 360 is provided with the display, and presentsthe operation information on the display.

When the filament deteriorates and the amount of the thermoelectronemitted therefrom reduces, the G1 voltage value, which is controlled toobtain the preset tube current value, increases. Owing to this, theX-ray tube operation status acquiring unit 3 can detect thedeterioration of the filament 110 by comparing the G1 voltage value ofthe operation information under the preset tube current value and the G1voltage value (initial value). As a result, the cause of failure(deterioration of the filament 110) of the X-ray tube 1 can be detectedwithout work or time of service person. By receiving a notificationtransmitted from the notification section 350 with the informationcommunication terminal 4, it is possible for service person to notifythe deterioration of the filament 110 to the user before the filament110 reaches the end of life without work or time to prompt thepreparation for replacement of the filament (in the case of sealed type,the X-ray tube head). By presenting the operation information on thedisplay, service person can obtain the information about the operationstatus of the X-ray tube 1.

Next, a third operation (an operation in which the attrition degreedetermination section 330 determines the degree of attrition of thetarget 150 based on the X-ray irradiation time) of the X-ray tubeoperation status acquiring system according to the first embodiment andthe effect thereof will be described.

When the X-ray irradiation switch 22 of the X-ray tube controller 2turns ON, the level of the grid voltage applied to the first gridelectrode reaches the G1 voltage value, and the tube current, which ispreset for the target 150, flows. The measuring section 220 counts thetime (X-ray irradiation time) from a point when the X-ray irradiationswitch 22 turns ON. The memory 230 stores the X-ray irradiation timecounted by the measuring section 220. The X-ray irradiation time storedin the memory 230 is transmitted by the communication section 210 to theX-ray tube operation status acquiring unit 3 at intervals of 1 second.Further, when the X-ray irradiation switch 22 turns ON, thecommunication section 210 transmits the date and time (X-ray irradiationstart date and time); and when the X-ray irradiation switch 22 turnsOFF, the communication section 210 transmits the date and time (X-rayirradiation terminate date and time) to the X-ray operation statusacquiring unit 3.

When the communication section 310 of the X-ray tube operation statusacquiring unit 3 receives the operation information (the X-rayirradiation time, the X-ray irradiation start date and time and theX-ray irradiation terminate date and time), the storage section 320stores the operation information. FIG. 5 is a diagram showing thecontent of a file 323 about the X-ray irradiation time of the X-ray tube1, which is included in the operation information. As shown in FIG. 5,the file 323 comprises an X-ray irradiation start date and time field,an X-ray irradiation terminate date and time field and an X-rayirradiation time field. The operation information is written in therelated field in the file 323.

The attrition degree determination section 330 counts the X-rayirradiation time with reference to the file 323. In the storage section320, a database, written with the degree of attrition corresponding tothe integrated X-ray irradiation time (the reduction ratio of the X-raydosage under a predetermined tube voltage value and tube current valuerelative to the initial value (X-ray amount when the target 150 is firstput to use)) is stored. The attrition degree determination section 330determines the degree of attrition of the target 150 from the countedX-ray irradiation time with reference to the database.

When the degree of attrition of the target 150 to be determined by theattrition degree determination section 330 has reached a predeterminedvalue (for example, the count of the X-ray irradiation time: 5,000hours, degree of attrition of the target 150: 30%), the notificationsection 350 transmits a notification to prompt replacement or rotationof the target 150, (in the case of the sealed type, X-ray tube head) tothe information communication terminal 4. By rotating the target 150,the point where the thermoelectron beam hits in the target 150 ischanged; thus, the X-ray dosage can be recovered by the rotation of thetarget 150.

The presentation section 360 is provided with the display, and presentsthe file 323 on the display.

When the tube voltage value and the tube current value are substantiallyconstant, the target 150 deteriorates in proportion to the count of theX-ray irradiation time. Therefore, the X-ray tube operation statusacquiring unit 3 can detect the deterioration of the target 150 from thecount of the X-ray irradiation time. As a result, it is possible forservice person to detect the cause of failure (deterioration of thetarget 150) of the X-ray tube 1 without work or time. By receiving thenotification transmitted by the notification section 350 with theinformation communication terminal 4, it is possible for service personto prompt the user to replace or rotate the target 150 (in the case ofthe sealed type, replacement of the X-ray tube head) before the target150 gets damaged without work or time. By presenting the operationinformation on the display, service person can obtain the informationabout the operation status of the X-ray tube 1.

Next, a fourth operation (an operation in which the attrition degreedetermination section 330 determines the degree of attrition of thetarget 150 based on the level of the tube voltage and the over-timechanges in the strength of the tube current) of the X-ray tube operationstatus acquiring system according to the first embodiment and the effectthereof will be described.

When the X-ray irradiation switch 22 of the X-ray tube controller 2turns ON, the measuring section 220 measures the tube voltage value andtube current value. The memory 230 stores the tube voltage value and thetube current value measured by the measuring section 220. The tubevoltage value and the tube current value stored in the memory 230 aretransmitted to the X-ray tube operation status acquiring unit 3 alongwith the transmission date and time by the communication section 210 atintervals of 1 second.

When the communication section 310 of the X-ray tube operation statusacquiring unit 3 receives the operation information (the tube voltagevalue and the tube current value), the storage section 320 stores theoperation information. FIG. 6 is a diagram showing the content of a file324 about the over-time changes of the tube voltage value and the tubecurrent value included in the operation information. As shown in FIG. 6,the file 324 comprises a date and time field, a tube voltage value fieldand a tube current value field. In the date and time field, transmissiondate and time of the operation information is written; in the tubevoltage value field and the tube current value field, the tube voltagevalue and the tube current value of the operation information arewritten. Further, in the storage section 320, a database written withdegree of attrition of the target 150 at intervals of 1 second (thereduction ratio of the X-ray dosage under a predetermined tube voltagevalue and tube current value relative to the initial value (X-ray dosagewhen the target 150 is first put to use)) in a combination of the tubevoltage value and the tube current value is stored.

The attrition degree determination section 330 extracts degree ofattrition at intervals of 1 second under the tube voltage value and thetube current value in the file 324 with reference to the above database,and determines the degree of attrition of the target 150 by integratingthe attrition.

When the degree of attrition of the target 150 to be determined by theattrition degree determination section 330 has reached a predeterminedvalue (for example, degree of attrition of the target 150: 30%), thenotification section 350 transmits a notification to prompt replacementor rotation of the target 150, (in the case of the sealed type, X-raytube head) to the information communication terminal 4.

The presentation section 360 is provided with the display, and presentsthe file 324 on the display.

By determining the degree of attrition of the target 150 from theover-time changes of the tube voltage value and the tube current value,even when the tube voltage value and the tube current value change, theX-ray tube operation status acquiring unit 3 can detect thedeterioration of the target 150 precisely. As a result, it is possiblefor service person to detect the cause of failure (deterioration of thetarget 150) of the X-ray tube 1 without work or time. By receiving thenotification transmitted by the notification section 350 with theinformation communication terminal 4, it is possible for service personto prompt the user to replace or rotate the target 150 (in the case ofthe sealed type, replacement of the X-ray tube head) before the target150 gets damaged without work or time. By presenting the operationinformation on the display, service person can obtain the informationabout the operation status of the X-ray tube 1.

Next, a fifth operation (an operation in which the attrition degreedetermination section 330 determines the degree of attrition of thetarget 150 based on the strength of the X-ray) of the X-ray tubeoperation status acquiring system according to the first embodiment andthe effect thereof will be described.

When the power switch 21 of the X-ray tube controller 2 turns ON, thewarming up of the X-ray tube 1 begins. The measuring section 220 (X-raymonitor 221) measures the strength (X-ray dosage) of the X-ray duringthe warming up. The memory 230 stores the X-ray dosage measured by themeasuring section 220, the tube voltage value and the tube currentvalue. When the activation of the X-ray tube 1 is terminated, the X-raydosage, the tube voltage value and the tube current value stored in thememory 230 are transmitted to the X-ray tube operation status acquiringunit 3.

When the communication section 310 of the X-ray tube operation statusacquiring unit 3 receives the operation information (X-ray dosage, tubevoltage value and the tube current value), the storage section 320stores the operation information.

FIG. 7 is a diagram showing the content of a file 325 about therelationship among the tube voltage value, the tube current value andthe X-ray dosage (initial value) of the X-ray tube 1 stored in thestorage section 320. As shown in FIG. 7, the file 325 comprises a tubevoltage value field, a tube current field and an X-ray dosage field. Inthe X-ray dosage field, the initial value of the X-ray dosage at therelevant tube voltage value and tube current value is written.

The attrition degree determination section 330 extracts the X-ray dosage(initial value) at the tube voltage value and tube current value in theoperation information with reference to the file 325 and compares itwith the X-ray dosage in the operation information. Thereby, the degreeof attrition of the target 150 (the reduction ratio of the X-ray dosageat a predetermined tube voltage value and tube current value relative tothe initial value (when the target 150 is put to use)) is determined.

When the degree of attrition of the target 150 to be determined by theattrition degree determination section 330 has reached a predeterminedvalue (for example, degree of attrition of the target 150: 30%), thenotification section 350 transmits a notification to prompt replacementor rotation of the target 150, (in the case of the sealed type, X-raytube head)to the information communication terminal 4.

The presentation section 360 is provided with the display, and presentsthe operation information on the display.

When the target 150 deteriorates, the X-ray dosage generated underspecific tube voltage value and tube current value decreases. Therefore,the X-ray tube operation status acquiring unit 3 can detect thedeterioration of the target 150 by comparing the X-ray dosage (initialvalue) at the tube voltage value and tube current value in the operationinformation with the X-ray dosage in the operation information. As aresult, it is possible for service person to detect the cause of failure(deterioration of the target 150) of the X-ray tube 1 without work ortime. By receiving the notification transmitted from the notificationsection 350 with the information communication terminal 4, it ispossible for service person to prompt the user to replace or rotate thetarget (in the case of sealed type, replacement of the X-ray tube head)before the target 150 gets damaged without work or time. By presentingthe operation information on the display, it is possible for serviceperson to obtain the information about the operation status of the X-raytube 1.

Next, a sixth operation (an operation in which the abnormal operationdetecting section 340 detects the electric discharge phenomenon in theX-ray tube 1 based on the strength of the X-ray) of the X-ray tubeoperation status acquiring system according to the first embodiment andthe effect thereof will be described.

When the X-ray irradiation switch 22 of the X-ray tube controller 2turns ON, the tube current flows to the target 150, and the X-ray isirradiated. The measuring section 220 (X-ray monitor 221) measures thestrength (X-ray dosage) of the X-ray. The memory 230 stores the X-raydosage measured by the measuring section 220 and the preset tube voltagevalue and the tube current value. The X-ray dosage, the tube voltagevalue and the tube current value stored in the memory 230 aretransmitted to the X-ray tube operation status acquiring unit 3 by thecommunication section 210 at intervals of 1 second.

When the communication section 310 of the X-ray tube operation statusacquiring unit 3 receives the operation information (the tube voltagevalue, the tube current value and the X-ray dosage), the storage section320 stores the operation information.

FIG. 8 is a diagram showing the content of a file 326 about the tubevoltage value, the tube current value and the X-ray dosage included inthe operation information. As shown in FIG. 8, the file 326 comprises atube voltage value field, a tube current value field and an X-ray dosagefield. The operation information is written in the relevant field.

The abnormal operation detecting section 340 computes the reductionratio of the X-ray dosage at intervals of 1 second with reference to thefile 326. When the reduction ratio of the X-ray dosage at specific tubevoltage value and tube current value exceeds a predetermined value, theabnormal operation detecting section 340 detects electric dischargephenomenon in the X-ray tube 1.

When electric discharge phenomenon in the X-ray tube 1 is detected bythe abnormal operation detecting section 340, the notification section350 transmits an alarm that the electric discharge phenomenon hasoccurred to the information communication terminal 4.

The presentation section 360 is provided with the display, and presentsthe file 326 on the display.

When electric discharge phenomenon occurs in the X-ray tube 1, since thetarget 150 deteriorates, the X-ray dosage generated under specific tubevoltage value and tube current value decreases. Therefore, the X-raytube operation status acquiring unit 3 can detect the electric dischargephenomenon in the X-ray tube 1 from the fact that the X-ray dosagechanges sharply at specific tube voltage value and tube current value.As a result, it is possible for service person to detect the cause offailure (occurrence of the electric discharge phenomenon) in the X-raytube 1 without work or time. By receiving the alarm transmitted by thenotification section 350 with the information communication terminal 4,it is possible for service person to raise an alarm to the user aboutthe occurrence of the electric discharge phenomenon before the controlsystem or the target 150 of the X-ray tube 1 gets damaged by theelectric discharge phenomenon without work or time. By presenting theoperation information on the display, it is possible for service personto obtain the information about the operation status of the X-ray tube1.

Second Embodiment

FIG. 9 is a diagram showing the functional configuration of an X-raytube operation status acquiring system according to a second embodiment.The configuration of the X-ray tube unit and the X-ray tube operationstatus acquiring unit 3 is the same as that in the first embodiment. Inthe second embodiment, however, the tube voltage value and the tubecurrent value of the X-ray tube 1 are fixed. In the second embodiment,the operation record (operation information) is stored in the memory230. When service person visits the installation site of the X-ray tube1, the service person connects a laptop PC 5 to the X-ray tubecontroller 2 to read the operation record stored in the memory 230 tothe laptop PC 5. After that, the service person connects the laptop PC 5to a communication line to transfer the operation record to the X-raytube operation status acquiring unit 3.

In the operation record, information such as the filament power supplytime, the X-ray irradiation time, changes of the G1 voltage value, andchanges of the X-ray dosage is included. FIG. 10A is a graph showing thefilament power supply time. FIG. 10B is a graph showing the X-rayirradiation time. FIG. 10C is a graph showing changes of the G1 voltagevalue. FIG. 10D is a graph showing changes of the X-ray dosage (strengthof the X-ray). In FIGS. 10A-D, an example, in which after the previouscollection of the operation record was carried out at 0:00 on Apr. 1,2003, the first activation of the X-ray tube 1 was made; and thecollection of the operation record this time is made at 12:00 on Apr. 3,2005, is shown.

By carrying out the same operation as that in the first embodiment, theattrition degree determination section 330 determines degree ofattrition of the filament 110 from the filament power supply timeincluded in the operation record. By comparing the latest G1 voltagevalue with a threshold −Vth [V], the attrition degree determinationsection determines the end of life of the filament 110. In FIG. 10D, theX-ray dosage is maintained over a threshold Xth. But, in FIG. 10C, sincethe latest G1 voltage value is higher than the threshold −Vth [V], it isdetermined that the end of life of the filament 110 has been reached.

By carrying out the same operation as that in the first embodiment, theattrition degree determination section 330 determines the degree ofattrition of the target 150 from the X-ray irradiation time included inthe operation record. Also, when the latest X-ray dosage is lower thanthe threshold Xth, the attrition degree determination section 330determines that the end of life of the target 150 has been reached.

The above determination result by the attrition degree determinationsection 330 is transmitted to the laptop PC 5 via the communicationline. Based on the determination result transmitted to the laptop PC 5,service person can notify the user of the status of the X-ray tube 1.

As a modification of the present embodiment, the following example isconceivable. That is, the X-ray tube controller is provided with anattrition degree determination section, and the attrition degreedetermination section determines the degree of attrition of the filamentand target and occurrence of electric discharge phenomenon from theoperation record stored in a memory.

INDUSTRIAL APPLICABILITY

The X-ray tube operation status acquiring unit and the X-ray tubeoperation status acquiring method of the present invention areapplicable to, for example, the control of medical X-ray generators.

1. An X-ray tube operation status acquiring unit, comprising: receiving means for receiving operation information about operation status of an X-ray tube transmitted from an X-ray tube measuring apparatus for measuring the operation status of said X-ray tube via a communication line, and storing means for storing said operation information received by said receiving means.
 2. The X-ray tube operation status acquiring unit according to claim 1, wherein said operation information includes filament power supply time.
 3. The X-ray tube operation status acquiring unit according to claim 1 or 2, in which said operation information includes a level of a grid voltage applied to grid electrodes so as to maintain the value of the tube current flowing to a target to a certain level in a state where a predetermined tube voltage is applied to said target of said X-ray tube.
 4. The X-ray tube operation status acquiring unit according to claim 1, wherein said operation information includes X-ray irradiation time.
 5. The X-ray tube operation status acquiring unit according to claim 1 or 4, in which said operation information includes a level of the tube voltage applied to the target of said X-ray tube and a strength of the tube current flowing to said target.
 6. The X-ray tube operation status acquiring unit according to claim 1 or 4, in which said operation information includes a strength of the X-ray generated by thermoelectron collided with said target in a state where a predetermined tube voltage is applied to the target of said X-ray tube and a predetermined tube current flows to said target.
 7. The X-ray tube operation status acquiring unit as in any of claims 1-6, further comprising attrition degree determination means for determining the degree of attrition of component constituting said X-ray tube based on said operation information.
 8. The X-ray tube operation status acquiring unit according to claim 7, in which said X-ray tube is provided with a filament for emitting thermoelectron by being supplied with power; said operation information includes filament power supply time; said attrition degree determination means determines the degree of attrition of said filament based on said filament power supply time.
 9. The X-ray tube operation status acquiring unit according to claim 7 or 8, in which said X-ray tube is provided with a filament for emitting thermoelectron by being supplied with power; said operation information includes a level of a grid voltage applied to grid electrodes so as to maintain the value of the tube current flowing to said target to a certain level in a state where a predetermined tube voltage is applied to the target of said X-ray tube; said attrition degree determination means determines the degree of attrition of said filament based on the level of said grid voltage.
 10. The X-ray tube operation status acquiring unit as in any of claims 7-9, in which said operation information includes X-ray irradiation time; said attrition degree determination means determines the degree of attrition of the target of said X-ray tube based on said X-ray irradiation time.
 11. The X-ray tube operation status acquiring unit as in any of claims 7-10, in which said operation information includes a level of the tube voltage applied to the target of said X-ray tube and a strength of the tube current flowing to said target; said attrition degree determination means determines the degree of attrition of said target based on the over-time changes of the level of said tube voltage and the strength of said tube current.
 12. The X-ray tube operation status acquiring unit as in any of claims 7-11, in which said operation information includes a strength of the X-ray generated by thermoelectron collided with said target in a state where a predetermined tube voltage is applied to the target of said X-ray tube and a predetermined tube current flows to said target; said attrition degree determination means determines the degree of attrition of said target based on the strength of said X-ray.
 13. The X-ray tube operation status acquiring unit as in any of claims 7-12, further comprising determination result notifying means for notifying determination result by said attrition degree determination means to an information communication terminal via a communication line.
 14. The X-ray tube operation status acquiring unit as in any of claims 1-13, further comprising abnormal operation detecting means for detecting abnormal operation of said X-ray tube based on said operation information.
 15. The X-ray tube operation status acquiring unit according to claim 14, wherein said operation information includes a strength of the X-ray generated by thermoelectron collided with said target of said X-ray tube in a state where a predetermined tube voltage is applied to the target of said X-ray tube and a predetermined tube current flows to said target; said abnormal operation detecting means detects occurrence of electric discharge phenomenon in said X-ray tube based on the strength of said X-ray.
 16. The X-ray tube operation status acquiring unit according to claim 14 or 15, further comprising detection result notifying means for notifying detection result by said abnormal operation detecting means to an information communication terminal via a communication line.
 17. The X-ray tube operation status acquiring unit as in any of claims 1-16, further comprising presentation means for presenting said operation information stored in said storing means on a display.
 18. An X-ray tube operation status acquiring system for controlling the operation status of an X-ray tube, comprising: an X-ray tube measuring apparatus including measuring means for measuring operation status of said X-ray tube and transmission means for transmitting operation information of said X-ray tube obtained by said measuring means by measuring the operation status of said X-ray tube to an information communication terminal via a communication line, and X-ray tube operation status acquiring unit as in any of claims 1-17, wherein receiving means of said X-ray tube operation status acquiring unit receives said operation information transmitted by transmission means of said X-ray tube measuring apparatus; storing means of said X-ray tube operation status acquiring unit stores said operation information received by the receiving means of said X-ray tube operation status acquiring unit.
 19. An X-ray tube operation status acquiring method, comprising: a receiving step in which receiving means receives operation information about operation status of said X-ray tube transmitted from an X-ray tube measuring apparatus for measuring the operation status of the X-ray tube via a communication line, and a storing step in which storing means stores said operation information received by said receiving means.
 20. The X-ray tube operation status acquiring method according to claim 19, wherein said operation information includes filament power supply time.
 21. The X-ray tube operation status acquiring method according to claim 19 or 20, in which said operation information includes a level of a grid voltage applied to grid electrodes so as to maintain the value of the tube current flowing to said target to a certain level in a state where a predetermined tube voltage is applied to the target of said X-ray tube.
 22. The X-ray tube operation status acquiring method according to claim 19, wherein said operation information includes X-ray irradiation time.
 23. The X-ray tube operation status acquiring method according to claim 19 or 22, in which said operation information includes a level of the tube voltage applied to the target of said X-ray tube and a strength of the tube current flowing to said target.
 24. The X-ray tube operation status acquiring method according to claim 19 or 22, in which said operation information includes a strength of the X-ray generated by thermoelectron collided with said target in a state where a predetermined tube voltage is applied to the target of said X-ray tube and a predetermined tube current flows to said target.
 25. The X-ray tube operation status acquiring method as in any of claims 19-24, further comprising an attrition degree determination step in which attrition degree determination means determines the degree of attrition of component constituting said X-ray tube based on said operation information.
 26. The X-ray tube operation status acquiring method according to claim 25, in which said X-ray tube is provided with a filament for emitting thermoelectron by being supplied with power; said operation information includes filament power supply time; said attrition degree determination means determines the degree of attrition of said filament based on said filament power supply time.
 27. The X-ray tube operation status acquiring method according to claim 25 or 26, in which said X-ray tube is provided with a filament for emitting thermoelectron by being supplied with power; said operation information includes a level of a grid voltage applied to grid electrodes so as to maintain the value of the tube current flowing to said target to a certain level in a state, where a predetermined tube voltage is applied to the target of said X-ray tube; said attrition degree determination means determines the degree of attrition of said filament based on the level of said grid voltage.
 28. The X-ray tube operation status acquiring method as in any of claims 25-27, in which said operation information includes X-ray irradiation time; said attrition degree determination means determines the degree of attrition of the target of said X-ray tube based on said X-ray irradiation time.
 29. The X-ray tube operation status acquiring method as in any of claims 25-28, in which said operation information includes a level of the tube voltage applied to the target of said X-ray tube and a strength of the tube current flowing to said target; said attrition degree determination means determines the degree of attrition of said target based on the over-time changes of the level of said tube voltage and the strength of said tube current.
 30. The X-ray tube operation status acquiring method as in any of claims 25-29, in which said operation information includes strength of the X-ray generated by thermoelectron collided with said target in a state where a predetermined tube voltage is applied to the target of said X-ray tube and a predetermined tube current flows to said target; said attrition degree determination means determines the degree of attrition of said target based on the strength of said X-ray.
 31. The X-ray tube operation status acquiring method as in any of claims 25-30, further comprising a determination result notifying step, in which determination result notifying means notifies determination result by said attrition degree determination means to an information communication terminal via a communication line.
 32. The X-ray tube operation status acquiring method as in any of claims 19-31, further comprising an abnormal operation detecting step, in which abnormal operation detecting means detects abnormal operation of said X-ray tube based on said operation information.
 33. The X-ray tube operation status acquiring method according to claim 32, wherein said operation information includes a strength of the X-ray generated by thermoelectron collided with said target of said X-ray tube in a state where a predetermined tube voltage is applied to the target of said X-ray tube and a predetermined tube current flows to said target; said abnormal operation detecting means detects occurrence of electric discharge phenomenon in said X-ray tube based on the strength of said X-ray.
 34. The X-ray tube operation status acquiring method according to claim 32 or 33, further comprising a detection result notifying step, in which detection result notifying means notifies detection result by said abnormal operation detecting means to an information communication terminal via a communication line.
 35. The X-ray tube operation status acquiring method as in any of claims 19-34, further comprising a presentation step, in which presentation means presents said operation information stored in said storing means on a display.
 36. An X-ray tube operation status acquiring unit for obtaining operation information about operation status of an X-ray tube equipped with a filament for emitting thermoelectron by being supplied with power, comprising: inputting means for inputting operation information of said X-ray tube outputted from an X-ray tube measuring apparatus for measuring operation status of said X-ray tube and including at least filament power supply time and value of grid voltage applied to grid electrodes so as to maintain the value of tube current flowing to a target in a state where a predetermined tube voltage is applied to said target of said X-ray tube, and attrition degree determination means for determining degree of attrition of said filament based on said filament power supply time and said grid voltage value.
 37. An X-ray tube operation status acquiring unit for obtaining operation information about operation status of an X-ray tube, comprising: inputting means for inputting operation information of said X-ray tube outputted from an X-ray tube measuring apparatus for measuring operation status of said X-ray tube and including at lest X-ray irradiation time and strength of X-ray generated by thermoelectron collided with a target in a state where a predetermined tube voltage is applied to said target of said X-ray tube and a predetermined tube current flows to said target, and attrition degree determination means for determining degree of attrition of said target based on said X-ray irradiation time and the strength of said X-ray.
 38. An X-ray tube operation information acquiring method for obtaining operation information about operation status of an X-ray tube equipped with a filament for emitting thermoelectron by being supplied with power, comprising: a first step for obtaining operation information of said X-ray tube outputted from an X-ray tube measuring apparatus for measuring operation status of said X-ray tube and including at least filament power supply time and a value of grid voltage applied to grid electrodes so as to maintain the value of tube current flowing to a target in a state where a predetermined tube voltage is applied to said target of said X-ray tube, and a second step for determining degree of attrition of said filament based on said filament power supply time and said grid voltage value.
 39. An X-ray tube operation information acquiring method for obtaining operation information about operation status of an X-ray tube, comprising: a first step for obtaining operation information of said X-ray tube outputted from an X-ray tube measuring apparatus for measuring operation status of said X-ray tube and including at lest X-ray irradiation time and a strength of X-ray generated by thermoelectron collided with a target in a state where a predetermined tube voltage is applied to said target of said X-ray tube and a predetermined tube current flows to said target, and a second step for determining degree of attrition of said target based on said X-ray irradiation time and the strength of said X-ray. 